User manual

Operation
Liebert
®
iCOM
®
42
S136 DT1 (Room / Outdoor) Value—Field-adjustable setpoint or temperature. The type (setpoint
or temperature) is based on the setting on S135.
S137 DT2 (Room / FC Fluid) Type—Determines the method to activate the water circuit on dual-
cool and free-cool units. When this parameter is set to “Contact,” a dry contact closure can be used to
activate the free-cooling circuit. When this parameter is set to “Value,” the delta between the water
temperature of the free-cooling circuit and the actual room temperature are compared.
S138 DT2 Room / FC Fluid) Value—Sets the delta between the actual room temperature and the
free-cooling fluid temperature to determine if cooling can be provided.
S139 Minimum CW Temp—Enables the temperature at which free-cooling can operate
independently without assistance of the compressor circuit.
S140 Minimum CW Temp Value—Sets the water temperature at which 100% free-cooling can be
provided to handle the full room load. When the fluid temperature is below this setting then the
compressors will no longer turn On until the water temperature is above the minimum CW Temp.
S141 Lockout FC at FC Fluid below—The temperature that turns Off the free-cooling circuit
when the water temperature is too low. This setting prevents frost from building up on the free-
cooling pipes when the outdoor ambient is extremely low.
Figure 37 Service/Economizer, page 1 of 3
SA02
Enable Economizer—Sets the Liebert Air Economizer
™
operation to one of the following
modes. These selections only determine if the Liebert Air Economizer is available for use; they do not
determine or override damper position. Damper position is always controlled by the sensor set to
control temperature (i.e., Return / Supply Sensor)
• Yes: This parameter will operate the Liebert Air Economizer based on the outdoor sensor reading
and will allow the Liebert iCOM to determine if the conditions are within the acceptable range of
operation.
• NO: This parameter will disable the Liebert Air Economizer and will not allow Liebert Air
Economizer to operate even if the outdoor conditions are acceptable.
• Remote: This parameter will enable the Liebert Air Economizer and ignore the outdoor Liebert
iCOM sensor even if the conditions are outside the range of operation.
SA04 Humidity Ratio—Sets the minimum and maximum limits of outdoor air based on the amount
of moisture content. The humidity ratio is set based on pounds of moisture per pound of dry air. This
is equivalent to the dew point temperatures.
SA05 Wet Bulb Temperature—Read-only value that displays the outdoor wet bulb temperature.
(This reading will be in metric values.)